Well-casing spear



o Mod-e1.) H M HOAGLAND.

WELL CASING SPEAR.

No. 569,378. Patented 0013.13, 1896.-

UNITED STATES PATENT OFFICE.

ELLERY M. IIOAGLAND, OF EAST OAKLAND, CALIFORNIA.

WELL-CASING SPEAR.

SPECIFICATION forming part of Letters Patent No. 569,378, dated October 13, 1896.

Appli ati 51 51 March 16, 1898. Serial No. 583,352. (No model.)

To (LU whom, it may concern:

Be it known that I, ELLERY M. HOAGLAND, a citizen of the United States, residing at East Oakland, county of Alameda, State of California, have invented an Improvement in ell-Casing Spears; and I hereby declare the following to be a full, clear, and exact description of the same.

My invention relates to the general class of well-boring tools, and especially to the class of casing-spears. The object of these spears is to take hold of and withdraw the casing. They consist of a stock which is let down within the casing by a suspending device, said stock being provided with gripping wedges or slips which by a wedging action when the stock is pulled up upon engage or grip the interior of the surface of the casing and hold tighter the harder they are pulled upon, so that the casing may be withdrawn.

My invention consists in certain improvements in spears of this character, said improvements consisting in novel means for setting or adjusting the wedges or slips and for readily releasing them from their grip on the casing.

The object of my invention is to provide a casing-spear the wedges of which may be readily initially adjusted to suit any sized casing, and which may be as easily released when it is necessary to take the spear out.

Referring to the accompanying drawings, Figure 1 is a vertical section of my spear. Fig. 2 is a side view. Fig. 3 is a cross-section through the cross-head E. Fig. 4c is a modification.

A is the stock of the spear, having means for connecting it above with the suspending devices, said stock being made hollow in its lower portion and provided with an elongated cross-slot a and with inclined wedge-seats a on each side, the planes of which converge upwardly.

B are the wedges or slips which are seated upon the inclined wedge-seats and by the movement thereof effect the wedging action common to this class of devices. The faces of these wedges are corrugated or roughened as usual.

0 are wearing-plates intervening between the wedge planes or seats of the stock and the wedges and on which the latter slide.

These plates are metallic and may serve to strengthen a wood stock. They are secured by screws, so that they may be readily removed to obtain access to the interior of the stock and to seat wedges or slips of different sizes.

A point of improvement in my spear consists in the manner in which the wedges or slips are secured to the stock. The wedges or slips have inwardlyextending ears Z), which pass into the slot a of the stock and take cross-pins b, which play behind the walls of the slot or the wearing-plate, so that the wedges or slips are held firmly in place and may slide freely up and down.

\Vithin the stock is fixed a spindle or rod D, which is formed 011 each side with a series of notches or teeth d, formed with straight upper walls or shoulders and with inclined faces joining said shoulders. Upon this rod or spindle is fitted and adapted to slide freely a cross-head E, having oppositely-extending hollow or tubular arms 6, which project out wardly through the slot at in the stock and wearing-plates. A spring F lies between the foot of the rod or spindle and the cross-head and controls the latter. The projecting arms of the cross-head fit into enlarged or oblong slots Z) in the wedges or slips B, and locking pins or pawls G are seated in said tubular arms and are adapted, when pushed inwardly, to engage with the straight shoulders of the teeth d of the rod or spindle D.

The operation and use of my spear as thus constructed are as follows: Before inserting the spear, the interior diameter of the casing to be removed being known, the wedges or slips B are forced down their inclined planes to such a position, as is indicated by the calipers, as to cause the spear to snugly fit the casing. The wedges or slips are then set in this position by taking a small instrument and forcing inwardly the locking pins or pawls G, so that they temporarily engage the teeth (1 of the rod D, and thus secure the wedges in the position to which they are adjusted. The spear is now let down into the casing and because of the snug fit therein the wedges or slips will move upwardly very slightly to the extent of their oblong slots 6 which fit freely over the arms of the cross-head, and this slight movement upwardly is sufficient to reduce the diameter of the spear enough to relieve the tight fit and permit the spear to go down into the casing to the point desired. Vhen this point is reached and the lowering of the suspending device and spearis stopped, the wedges or slips will drop down again of their own weight to the limit of their oblong slots, thus once more enlarging the spear to its adjusted diameter and fitting snugly within the casing. Now the tension or lifting force being applied, the stock moving up and the wedges or slips now gripping the pipe, they will tend to expand outwardly on their inclined-plane seats, so that the harder the strain of the lifting force the stronger their grip on the casing, and this upward tendency of the stock at the same time causes the locking pins or pawls to slip outwardly by the inclined faces of the teeth cl of the rod D, and being horizontal they have no tendency to move in again, and are thereby entirely free of the teeth of the rod, so that the wedges or slips are now unlocked, but continue their grip on the casing as long as the lifting strain is applied. The casing is thus drawn out and as soon as the lifting strain is relieved by slacking the strain on the tool the wedges or slips, being free, will be thrown upwardly by the spring to their smallest diameter, and thus the spear will be released. In the same manner the spear may be released at any time whether the casing has been moved or not. The operator thus has perfect control of the releasing of the spear and may do so at any time by simply lowering the tool.

Idonotconfine myself to the use of a spring such as F in all cases as a means tending to force and hold the wedges or slips upwardly, for, as I have shown in Fig. 4, I may use a suspended weight IV. In this case the rod or spindle D is hollow to accommodate the weight and its suspending -cord 20, which passes up over a pulley above and is at tached to the cross-head E.

Having thus described my invention, what I claim as new, and desire to secure by- Letters Patent, is-

1. In a casing-spear having a stock with inclined-plane seats, and slidable wedges or slips mounted thereon ,having elongated slots, a means tending to force and hold the wedges or slips upwardly, slidable locking-pins engaging said wedges or slips, and on which the latter have an independent vertical movement, and devices in the stock for engaging the locking-pins to hold and to release them.

2. In a casing-spear having a stock with inclined-plane seats, and slidable wedges or slips mounted thereon, a means tendingto force and hold the wedges or slips upwardly, locking-pins engaging said wedges or slips, and on which the latter have an independent vertical movement, and devices in the stock for engaging the locking-pins to hold and to release them, consisting of a rod or spindle within the stock having teeth with stopshoulders and inclined faces.

3. In a casing-spear having a stock with inclined-plane seats and slidable wedges or slips mounted thereon, the rod or spindle within the stock and having teeth, the springcontrolled sliding cross-head on said rod or spindle, and having hollow arms projecting outwardly and engaging the wedges or slips by means of fitting in an enlarged or oblong slot therein whereby the wedges or slips have an independent movement on said arms, and slidable locking pins or pawls seated in the arms and adapted, when forced inwardly, to engage with the teeth of the rod or spindle, and to be relieved therefrom by the downward movement of the cross-head.

4. In a casing-spear havinga slotted stock and inclined-plane seats with wedges or slips fitted thereon, the slotted removable wearing-plates on said inclined-plane seats andon which the wedges or slips slide, and the means for securing the wedges or slips consisting of the ears with cross-pins playing behind the slotted wearing-plates.

In witness whereof I have hereunto set my hand.

ELLERY M. HOAGLAND. lVitnesses:

S. H. NOURSE, JEssIE O. BRODIE. 

